Optical systems, such as those used a projection objective or an illumination system in a projection exposure apparatus for microlithography, are known. In some optical systems, a drive device, operated with piezoelectric elements can be used to help achieve desired imaging accuracy by active positioning of optical elements correspondingly provided with a drive device. In some instances, image aberrations can be addressed in this way. In certain cases, an arrangement of piezoelectric elements have been combined to form stacks, where one part of the piezoelectric elements has its direction of action perpendicular to the direction of movement and a second part has its direction of action parallel to the direction of movement.